could languish
Regular verb: languish - languished- languished

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could languish
you could languish
she could languish
we could languish
you could languish
they could languish 	I could be languishing
you could be languishing
she could be languishing
we could be languishing
you could be languishing
they could be languishing	I could have languished
you could have languished
she could have languished
we could have languished
you could have languished
they could have languished	I could have been languishing
you could have been languishing
she could have been languishing
we could have been languishing
you could have been languishing
they could have been languishing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't languish
you couldn't languish
she couldn't languish
we couldn't languish
you couldn't languish
they couldn't languish 	I couldn't be languishing
you couldn't be languishing
she couldn't be languishing
we couldn't be languishing
you couldn't be languishing
they couldn't be languishing	I couldn't have languished
you couldn't have languished
she couldn't have languished
we couldn't have languished
you couldn't have languished
they couldn't have languished	I couldn't have been languishing
you couldn't have been languishing
she couldn't have been languishing
we couldn't have been languishing
you couldn't have been languishing
they couldn't have been languishing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I languish?
could you languish?
could she languish?
could we languish?
could you languish?
could they languish? 	could I be languishing?
could you be languishing?
could she be languishing?
could we be languishing?
could you be languishing?
could they be languishing? 	could I have languished?
could you have languished?
could she have languished?
could we have languished?
could you have languished?
could they have languished? 	could I have been languishing?
could you have been languishing?
could she have been languishing?
could we have been languishing?
could you have been languishing?
could they have been languishing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I languish?
couldn't you languish?
couldn't she languish?
couldn't we languish?
couldn't you languish?
couldn't they languish? 	couldn't I be languishing?
couldn't you be languishing?
couldn't she be languishing?
couldn't we be languishing?
couldn't you be languishing?
couldn't they be languishing? 	couldn't I have languished?
couldn't you have languished?
couldn't she have languished?
couldn't we have languished?
couldn't you have languished?
couldn't they have languished? 	couldn't I have been languishing?
couldn't you have been languishing?
couldn't she have been languishing?
couldn't we have been languishing?
couldn't you have been languishing?
couldn't they have been languishing?